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Configuration File

The Supervisor configuration file is conventionally named :file:`supervisord.conf`. It is used by both :program:`supervisord` and :program:`supervisorctl`. If either application is started without the -c option (the option which is used to tell the application the configuration filename explicitly), the application will look for a file named :file:`supervisord.conf` within the following locations, in the specified order. It will use the first file it finds.

  1. :file:`$CWD/supervisord.conf`
  2. :file:`$CWD/etc/supervisord.conf`
  3. :file:`/etc/supervisord.conf`
  4. :file:`../etc/supervisord.conf` (Relative to the executable)
  5. :file:`../supervisord.conf` (Relative to the executable)

:file:`supervisord.conf` is a Windows-INI-style (Python ConfigParser) file. It has sections (each denoted by a [header]) and key / value pairs within the sections. The sections and their allowable values are described below.

Note

Some distributions have packaged Supervisor with their own customizations. These modified versions of Supervisor may load the configuration file from locations other than those described here. Notably, Ubuntu packages have been found that use /etc/supervisor/supervisord.conf.

[unix_http_server] Section Settings

The :file:`supervisord.conf` file contains a section named [unix_http_server] under which configuration parameters for an HTTP server that listens on a UNIX domain socket should be inserted. If the configuration file has no [unix_http_server] section, a UNIX domain socket HTTP server will not be started. The allowable configuration values are as follows.

[unix_http_server] Section Values

file

A path to a UNIX domain socket (e.g. :file:`/tmp/supervisord.sock`) on which supervisor will listen for HTTP/XML-RPC requests. :program:`supervisorctl` uses XML-RPC to communicate with :program:`supervisord` over this port. This option can include the value %(here)s, which expands to the directory in which the :program:`supervisord` configuration file was found.

Default: None.

Required: No.

Introduced: 3.0

chmod

Change the UNIX permission mode bits of the UNIX domain socket to this value at startup.

Default: 0700

Required: No.

Introduced: 3.0

chown

Change the user and group of the socket file to this value. May be a UNIX username (e.g. chrism) or a UNIX username and group separated by a colon (e.g. chrism:wheel).

Default: Use the username and group of the user who starts supervisord.

Required: No.

Introduced: 3.0

username

The username required for authentication to this HTTP server.

Default: No username required.

Required: No.

Introduced: 3.0

password

The password required for authentication to this HTTP server. This can be a cleartext password, or can be specified as a SHA-1 hash if prefixed by the string {SHA}. For example, {SHA}82ab876d1387bfafe46cc1c8a2ef074eae50cb1d is the SHA-stored version of the password "thepassword".

Note that hashed password must be in hex format.

Default: No password required.

Required: No.

Introduced: 3.0

[unix_http_server] Section Example

[unix_http_server]
file = /tmp/supervisor.sock
chmod = 0777
chown= nobody:nogroup
username = user
password = 123

[inet_http_server] Section Settings

The :file:`supervisord.conf` file contains a section named [inet_http_server] under which configuration parameters for an HTTP server that listens on a TCP (internet) socket should be inserted. If the configuration file has no [inet_http_server] section, an inet HTTP server will not be started. The allowable configuration values are as follows.

[inet_http_server] Section Values

port

A TCP host:port value or (e.g. 127.0.0.1:9001) on which supervisor will listen for HTTP/XML-RPC requests. :program:`supervisorctl` will use XML-RPC to communicate with :program:`supervisord` over this port. To listen on all interfaces in the machine, use :9001 or *:9001.

Default: No default.

Required: Yes.

Introduced: 3.0

username

The username required for authentication to this HTTP server.

Default: No username required.

Required: No.

Introduced: 3.0

password

The password required for authentication to this HTTP server. This can be a cleartext password, or can be specified as a SHA-1 hash if prefixed by the string {SHA}. For example, {SHA}82ab876d1387bfafe46cc1c8a2ef074eae50cb1d is the SHA-stored version of the password "thepassword".

Note that hashed password must be in hex format.

Default: No password required.

Required: No.

Introduced: 3.0

[inet_http_server] Section Example

[inet_http_server]
port = 127.0.0.1:9001
username = user
password = 123

[supervisord] Section Settings

The :file:`supervisord.conf` file contains a section named [supervisord] in which global settings related to the :program:`supervisord` process should be inserted. These are as follows.

[supervisord] Section Values

logfile

The path to the activity log of the supervisord process. This option can include the value %(here)s, which expands to the directory in which the supervisord configuration file was found.

Default: :file:`$CWD/supervisord.log`

Required: No.

Introduced: 3.0

logfile_maxbytes

The maximum number of bytes that may be consumed by the activity log file before it is rotated (suffix multipliers like "KB", "MB", and "GB" can be used in the value). Set this value to 0 to indicate an unlimited log size.

Default: 50MB

Required: No.

Introduced: 3.0

logfile_backups

The number of backups to keep around resulting from activity log file rotation. If set to 0, no backups will be kept.

Default: 10

Required: No.

Introduced: 3.0

loglevel

The logging level, dictating what is written to the supervisord activity log. One of critical, error, warn, info, debug, trace, or blather. Note that at log level debug, the supervisord log file will record the stderr/stdout output of its child processes and extended info info about process state changes, which is useful for debugging a process which isn't starting properly. See also: :ref:`activity_log_levels`.

Default: info

Required: No.

Introduced: 3.0

pidfile

The location in which supervisord keeps its pid file. This option can include the value %(here)s, which expands to the directory in which the supervisord configuration file was found.

Default: :file:`$CWD/supervisord.pid`

Required: No.

Introduced: 3.0

umask

The :term:`umask` of the supervisord process.

Default: 022

Required: No.

Introduced: 3.0

nodaemon

If true, supervisord will start in the foreground instead of daemonizing.

Default: false

Required: No.

Introduced: 3.0

minfds

The minimum number of file descriptors that must be available before supervisord will start successfully. A call to setrlimit will be made to attempt to raise the soft and hard limits of the supervisord process to satisfy minfds. The hard limit may only be raised if supervisord is run as root. supervisord uses file descriptors liberally, and will enter a failure mode when one cannot be obtained from the OS, so it's useful to be able to specify a minimum value to ensure it doesn't run out of them during execution. This option is particularly useful on Solaris, which has a low per-process fd limit by default.

Default: 1024

Required: No.

Introduced: 3.0

minprocs

The minimum number of process descriptors that must be available before supervisord will start successfully. A call to setrlimit will be made to attempt to raise the soft and hard limits of the supervisord process to satisfy minprocs. The hard limit may only be raised if supervisord is run as root. supervisord will enter a failure mode when the OS runs out of process descriptors, so it's useful to ensure that enough process descriptors are available upon :program:`supervisord` startup.

Default: 200

Required: No.

Introduced: 3.0

nocleanup

Prevent supervisord from clearing any existing AUTO child log files at startup time. Useful for debugging.

Default: false

Required: No.

Introduced: 3.0

childlogdir

The directory used for AUTO child log files. This option can include the value %(here)s, which expands to the directory in which the :program:`supervisord` configuration file was found.

Default: value of Python's :func:`tempfile.get_tempdir`

Required: No.

Introduced: 3.0

user

If :program:`supervisord` is run as the root user, switch users to this UNIX user account before doing any meaningful processing. This value has no effect if :program:`supervisord` is not run as root.

Default: do not switch users

Required: No.

Introduced: 3.0

directory

When :program:`supervisord` daemonizes, switch to this directory. This option can include the value %(here)s, which expands to the directory in which the :program:`supervisord` configuration file was found.

Default: do not cd

Required: No.

Introduced: 3.0

strip_ansi

Strip all ANSI escape sequences from child log files.

Default: false

Required: No.

Introduced: 3.0

environment

A list of key/value pairs in the form KEY="val",KEY2="val2" that will be placed in the :program:`supervisord` process' environment (and as a result in all of its child process' environments). This option can include the value %(here)s, which expands to the directory in which the supervisord configuration file was found. Values containing non-alphanumeric characters should be quoted (e.g. KEY="val:123",KEY2="val,456"). Otherwise, quoting the values is optional but recommended. To escape percent characters, simply use two. (e.g. URI="/first%%20name") Note that subprocesses will inherit the environment variables of the shell used to start :program:`supervisord` except for the ones overridden here and within the program's environment option. See :ref:`subprocess_environment`.

Default: no values

Required: No.

Introduced: 3.0

identifier

The identifier string for this supervisor process, used by the RPC interface.

Default: supervisor

Required: No.

Introduced: 3.0

[supervisord] Section Example

[supervisord]
logfile = /tmp/supervisord.log
logfile_maxbytes = 50MB
logfile_backups=10
loglevel = info
pidfile = /tmp/supervisord.pid
nodaemon = false
minfds = 1024
minprocs = 200
umask = 022
user = chrism
identifier = supervisor
directory = /tmp
nocleanup = true
childlogdir = /tmp
strip_ansi = false
environment = KEY1="value1",KEY2="value2"

[supervisorctl] Section Settings

The configuration file may contain settings for the :program:`supervisorctl` interactive shell program. These options are listed below.

[supervisorctl] Section Values

serverurl

The URL that should be used to access the supervisord server, e.g. http://localhost:9001. For UNIX domain sockets, use unix:///absolute/path/to/file.sock.

Default: http://localhost:9001

Required: No.

Introduced: 3.0

username

The username to pass to the supervisord server for use in authentication. This should be same as username from the supervisord server configuration for the port or UNIX domain socket you're attempting to access.

Default: No username

Required: No.

Introduced: 3.0

password

The password to pass to the supervisord server for use in authentication. This should be the cleartext version of password from the supervisord server configuration for the port or UNIX domain socket you're attempting to access. This value cannot be passed as a SHA hash. Unlike other passwords specified in this file, it must be provided in cleartext.

Default: No password

Required: No.

Introduced: 3.0

prompt

String used as supervisorctl prompt.

Default: supervisor

Required: No.

Introduced: 3.0

history_file

A path to use as the readline persistent history file. If you enable this feature by choosing a path, your supervisorctl commands will be kept in the file, and you can use readline (e.g. arrow-up) to invoke commands you performed in your last supervisorctl session.

Default: No file

Required: No.

Introduced: 3.0a5

[supervisorctl] Section Example

[supervisorctl]
serverurl = unix:///tmp/supervisor.sock
username = chris
password = 123
prompt = mysupervisor

[program:x] Section Settings

The configuration file must contain one or more program sections in order for supervisord to know which programs it should start and control. The header value is composite value. It is the word "program", followed directly by a colon, then the program name. A header value of [program:foo] describes a program with the name of "foo". The name is used within client applications that control the processes that are created as a result of this configuration. It is an error to create a program section that does not have a name. The name must not include a colon character or a bracket character. The value of the name is used as the value for the %(program_name)s string expression expansion within other values where specified.

Note

A [program:x] section actually represents a "homogeneous process group" to supervisor (as of 3.0). The members of the group are defined by the combination of the numprocs and process_name parameters in the configuration. By default, if numprocs and process_name are left unchanged from their defaults, the group represented by [program:x] will be named x and will have a single process named x in it. This provides a modicum of backwards compatibility with older supervisor releases, which did not treat program sections as homogeneous process group definitions.

But for instance, if you have a [program:foo] section with a numprocs of 3 and a process_name expression of %(program_name)s_%(process_num)02d, the "foo" group will contain three processes, named foo_00, foo_01, and foo_02. This makes it possible to start a number of very similar processes using a single [program:x] section. All logfile names, all environment strings, and the command of programs can also contain similar Python string expressions, to pass slightly different parameters to each process.

[program:x] Section Values

command

The command that will be run when this program is started. The command can be either absolute (e.g. /path/to/programname) or relative (e.g. programname). If it is relative, the program's directory and supervisord's environment $PATH will be searched for the executable. Programs can accept arguments, e.g. /path/to/program foo bar. The command line can use double quotes to group arguments with spaces in them to pass to the program, e.g. /path/to/program/name -p "foo bar". Note that the value of command may include Python string expressions, e.g. /path/to/programname --port=80%(process_num)02d might expand to /path/to/programname --port=8000 at runtime. String expressions are evaluated against a dictionary containing the keys group_name, host_node_name, process_num, program_name, here (the directory of the supervisord config file), and all supervisord's environment variables prefixed with ENV_. Controlled programs should themselves not be daemons, as supervisord assumes it is responsible for daemonizing its subprocesses (see :ref:`nondaemonizing_of_subprocesses`).

Default: No default.

Required: Yes.

Introduced: 3.0

process_name

A Python string expression that is used to compose the supervisor process name for this process. You usually don't need to worry about setting this unless you change numprocs. The string expression is evaluated against a dictionary that includes group_name, host_node_name, process_num, program_name, and here (the directory of the supervisord config file).

Default: %(program_name)s

Required: No.

Introduced: 3.0

numprocs

Supervisor will start as many instances of this program as named by numprocs. Note that if numprocs > 1, the process_name expression must include %(process_num)s (or any other valid Python string expression that includes process_num) within it.

Default: 1

Required: No.

Introduced: 3.0

numprocs_start

An integer offset that is used to compute the number at which numprocs starts.

Default: 0

Required: No.

Introduced: 3.0

priority

The relative priority of the program in the start and shutdown ordering. Lower priorities indicate programs that start first and shut down last at startup and when aggregate commands are used in various clients (e.g. "start all"/"stop all"). Higher priorities indicate programs that start last and shut down first.

Default: 999

Required: No.

Introduced: 3.0

autostart

If true, this program will start automatically when supervisord is started.

Default: true

Required: No.

Introduced: 3.0

autorestart

May be one of false, unexpected, or true. If false, the process will never be autorestarted. If unexpected, the process will be restart when the program exits with an exit code that is not one of the exit codes associated with this process' configuration (see exitcodes). If true, the process will be unconditionally restarted when it exits, without regard to its exit code.

Default: unexpected

Required: No.

Introduced: 3.0

startsecs

The total number of seconds which the program needs to stay running after a startup to consider the start successful. If the program does not stay up for this many seconds after it has started, even if it exits with an "expected" exit code (see exitcodes), the startup will be considered a failure. Set to 0 to indicate that the program needn't stay running for any particular amount of time.

Default: 1

Required: No.

Introduced: 3.0

startretries

The number of serial failure attempts that :program:`supervisord` will allow when attempting to start the program before giving up and putting the process into an FATAL state. See :ref:`process_states` for explanation of the FATAL state.

Default: 3

Required: No.

Introduced: 3.0

exitcodes

The list of "expected" exit codes for this program. If the autorestart parameter is set to unexpected, and the process exits in any other way than as a result of a supervisor stop request, :program:`supervisord` will restart the process if it exits with an exit code that is not defined in this list.

Default: 0,2

Required: No.

Introduced: 3.0

stopsignal

The signal used to kill the program when a stop is requested. This can be any of TERM, HUP, INT, QUIT, KILL, USR1, or USR2.

Default: TERM

Required: No.

Introduced: 3.0

stopwaitsecs

The number of seconds to wait for the OS to return a SIGCHILD to :program:`supervisord` after the program has been sent a stopsignal. If this number of seconds elapses before :program:`supervisord` receives a SIGCHILD from the process, :program:`supervisord` will attempt to kill it with a final SIGKILL.

Default: 10

Required: No.

Introduced: 3.0

stopasgroup

If true, the flag causes supervisor to send the stop signal to the whole process group and implies killasgroup is true. This is useful for programs, such as Flask in debug mode, that do not propagate stop signals to their children, leaving them orphaned.

Default: false

Required: No.

Introduced: 3.0b1

killasgroup

If true, when resorting to send SIGKILL to the program to terminate it send it to its whole process group instead, taking care of its children as well, useful e.g with Python programs using :mod:`multiprocessing`.

Default: false

Required: No.

Introduced: 3.0a11

user

If :program:`supervisord` runs as root, this UNIX user account will be used as the account which runs the program. If :program:`supervisord` can't switch to the specified user, the program will not be started.

Note

The user will be changed using setuid only. This does not start a login shell and does not change environment variables like USER or HOME. See :ref:`subprocess_environment` for details.

Default: Do not switch users

Required: No.

Introduced: 3.0

redirect_stderr

If true, cause the process' stderr output to be sent back to :program:`supervisord` on its stdout file descriptor (in UNIX shell terms, this is the equivalent of executing /the/program 2>&1).

Note

Do not set redirect_stderr=true in an [eventlistener:x] section. Eventlisteners use stdout and stdin to communicate with supervisord. If stderr is redirected, output from stderr will interfere with the eventlistener protocol.

Default: false

Required: No.

Introduced: 3.0, replaces 2.0's log_stdout and log_stderr

stdout_logfile

Put process stdout output in this file (and if redirect_stderr is true, also place stderr output in this file). If stdout_logfile is unset or set to AUTO, supervisor will automatically choose a file location. If this is set to NONE, supervisord will create no log file. AUTO log files and their backups will be deleted when :program:`supervisord` restarts. The stdout_logfile value can contain Python string expressions that will evaluated against a dictionary that contains the keys group_name, host_node_name, process_num, program_name, and here (the directory of the supervisord config file).

Note

It is not possible for two processes to share a single log file (stdout_logfile) when rotation (stdout_logfile_maxbytes) is enabled. This will result in the file being corrupted.

Default: AUTO

Required: No.

Introduced: 3.0, replaces 2.0's logfile

stdout_logfile_maxbytes

The maximum number of bytes that may be consumed by stdout_logfile before it is rotated (suffix multipliers like "KB", "MB", and "GB" can be used in the value). Set this value to 0 to indicate an unlimited log size.

Default: 50MB

Required: No.

Introduced: 3.0, replaces 2.0's logfile_maxbytes

stdout_logfile_backups

The number of stdout_logfile backups to keep around resulting from process stdout log file rotation. If set to 0, no backups will be kept.

Default: 10

Required: No.

Introduced: 3.0, replaces 2.0's logfile_backups

stdout_capture_maxbytes

Max number of bytes written to capture FIFO when process is in "stdout capture mode" (see :ref:`capture_mode`). Should be an integer (suffix multipliers like "KB", "MB" and "GB" can used in the value). If this value is 0, process capture mode will be off.

Default: 0

Required: No.

Introduced: 3.0, replaces 2.0's logfile_backups

stdout_events_enabled

If true, PROCESS_LOG_STDOUT events will be emitted when the process writes to its stdout file descriptor. The events will only be emitted if the file descriptor is not in capture mode at the time the data is received (see :ref:`capture_mode`).

Default: 0

Required: No.

Introduced: 3.0a7

stdout_syslog

If true, stdout will be directed to syslog along with the process name.

Default: False

Required: No.

Introduced: 4.0.0

stderr_logfile

Put process stderr output in this file unless redirect_stderr is true. Accepts the same value types as stdout_logfile and may contain the same Python string expressions.

Note

It is not possible for two processes to share a single log file (stderr_logfile) when rotation (stderr_logfile_maxbytes) is enabled. This will result in the file being corrupted.

Default: AUTO

Required: No.

Introduced: 3.0

stderr_logfile_maxbytes

The maximum number of bytes before logfile rotation for stderr_logfile. Accepts the same value types as stdout_logfile_maxbytes.

Default: 50MB

Required: No.

Introduced: 3.0

stderr_logfile_backups

The number of backups to keep around resulting from process stderr log file rotation. If set to 0, no backups will be kept.

Default: 10

Required: No.

Introduced: 3.0

stderr_capture_maxbytes

Max number of bytes written to capture FIFO when process is in "stderr capture mode" (see :ref:`capture_mode`). Should be an integer (suffix multipliers like "KB", "MB" and "GB" can used in the value). If this value is 0, process capture mode will be off.

Default: 0

Required: No.

Introduced: 3.0

stderr_events_enabled

If true, PROCESS_LOG_STDERR events will be emitted when the process writes to its stderr file descriptor. The events will only be emitted if the file descriptor is not in capture mode at the time the data is received (see :ref:`capture_mode`).

Default: false

Required: No.

Introduced: 3.0a7

stderr_syslog

If true, stderr will be directed to syslog along with the process name.

Default: False

Required: No.

Introduced: 4.0.0

environment

A list of key/value pairs in the form KEY="val",KEY2="val2" that will be placed in the child process' environment. The environment string may contain Python string expressions that will be evaluated against a dictionary containing group_name, host_node_name, process_num, program_name, and here (the directory of the supervisord config file). Values containing non-alphanumeric characters should be quoted (e.g. KEY="val:123",KEY2="val,456"). Otherwise, quoting the values is optional but recommended. Note that the subprocess will inherit the environment variables of the shell used to start "supervisord" except for the ones overridden here. See :ref:`subprocess_environment`.

Default: No extra environment

Required: No.

Introduced: 3.0

directory

A file path representing a directory to which :program:`supervisord` should temporarily chdir before exec'ing the child.

Default: No chdir (inherit supervisor's)

Required: No.

Introduced: 3.0

umask

An octal number (e.g. 002, 022) representing the umask of the process.

Default: No special umask (inherit supervisor's)

Required: No.

Introduced: 3.0

serverurl

The URL passed in the environment to the subprocess process as SUPERVISOR_SERVER_URL (see :mod:`supervisor.childutils`) to allow the subprocess to easily communicate with the internal HTTP server. If provided, it should have the same syntax and structure as the [supervisorctl] section option of the same name. If this is set to AUTO, or is unset, supervisor will automatically construct a server URL, giving preference to a server that listens on UNIX domain sockets over one that listens on an internet socket.

Default: AUTO

Required: No.

Introduced: 3.0

[program:x] Section Example

[program:cat]
command=/bin/cat
process_name=%(program_name)s
numprocs=1
directory=/tmp
umask=022
priority=999
autostart=true
autorestart=unexpected
startsecs=10
startretries=3
exitcodes=0,2
stopsignal=TERM
stopwaitsecs=10
stopasgroup=false
killasgroup=false
user=chrism
redirect_stderr=false
stdout_logfile=/a/path
stdout_logfile_maxbytes=1MB
stdout_logfile_backups=10
stdout_capture_maxbytes=1MB
stdout_events_enabled=false
stderr_logfile=/a/path
stderr_logfile_maxbytes=1MB
stderr_logfile_backups=10
stderr_capture_maxbytes=1MB
stderr_events_enabled=false
environment=A="1",B="2"
serverurl=AUTO

[include] Section Settings

The :file:`supervisord.conf` file may contain a section named [include]. If the configuration file contains an [include] section, it must contain a single key named "files". The values in this key specify other configuration files to be included within the configuration.

[include] Section Values

files

A space-separated sequence of file globs. Each file glob may be absolute or relative. If the file glob is relative, it is considered relative to the location of the configuration file which includes it. A "glob" is a file pattern which matches a specified pattern according to the rules used by the Unix shell. No tilde expansion is done, but *, ?, and character ranges expressed with [] will be correctly matched. Recursive includes from included files are not supported.

Default: No default (required)

Required: Yes.

Introduced: 3.0

[include] Section Example

[include]
files = /an/absolute/filename.conf /an/absolute/*.conf foo.conf config??.conf

[group:x] Section Settings

It is often useful to group "homogeneous" process groups (aka "programs") together into a "heterogeneous" process group so they can be controlled as a unit from Supervisor's various controller interfaces.

To place programs into a group so you can treat them as a unit, define a [group:x] section in your configuration file. The group header value is a composite. It is the word "group", followed directly by a colon, then the group name. A header value of [group:foo] describes a group with the name of "foo". The name is used within client applications that control the processes that are created as a result of this configuration. It is an error to create a group section that does not have a name. The name must not include a colon character or a bracket character.

For a [group:x], there must be one or more [program:x] sections elsewhere in your configuration file, and the group must refer to them by name in the programs value.

If "homogeneous" process groups (represented by program sections) are placed into a "heterogeneous" group via [group:x] section's programs line, the homogeneous groups that are implied by the program section will not exist at runtime in supervisor. Instead, all processes belonging to each of the homogeneous groups will be placed into the heterogeneous group. For example, given the following group configuration:

[group:foo]
programs=bar,baz
priority=999

Given the above, at supervisord startup, the bar and baz homogeneous groups will not exist, and the processes that would have been under them will now be moved into the foo group.

[group:x] Section Values

programs

A comma-separated list of program names. The programs which are listed become members of the group.

Default: No default (required)

Required: Yes.

Introduced: 3.0

priority

A priority number analogous to a [program:x] priority value assigned to the group.

Default: 999

Required: No.

Introduced: 3.0

[group:x] Section Example

[group:foo]
programs=bar,baz
priority=999

[fcgi-program:x] Section Settings

Supervisor can manage groups of FastCGI processes that all listen on the same socket. Until now, deployment flexibility for FastCGI was limited. To get full process management, you could use mod_fastcgi under Apache but then you were stuck with Apache's inefficient concurrency model of one process or thread per connection. In addition to requiring more CPU and memory resources, the process/thread per connection model can be quickly saturated by a slow resource, preventing other resources from being served. In order to take advantage of newer event-driven web servers such as lighttpd or nginx which don't include a built-in process manager, you had to use scripts like cgi-fcgi or spawn-fcgi. These can be used in conjunction with a process manager such as supervisord or daemontools but require each FastCGI child process to bind to its own socket. The disadvantages of this are: unnecessarily complicated web server configuration, ungraceful restarts, and reduced fault tolerance. With fewer sockets to configure, web server configurations are much smaller if groups of FastCGI processes can share sockets. Shared sockets allow for graceful restarts because the socket remains bound by the parent process while any of the child processes are being restarted. Finally, shared sockets are more fault tolerant because if a given process fails, other processes can continue to serve inbound connections.

With integrated FastCGI spawning support, Supervisor gives you the best of both worlds. You get full-featured process management with groups of FastCGI processes sharing sockets without being tied to a particular web server. It's a clean separation of concerns, allowing the web server and the process manager to each do what they do best.

Note

The socket manager in Supervisor was originally developed to support FastCGI processes but it is not limited to FastCGI. Other protocols may be used as well with no special configuration. Any program that can access an open socket from a file descriptor (e.g. with socket.fromfd in Python) can use the socket manager. Supervisor will automatically create the socket, bind, and listen before forking the first child in a group. The socket will be passed to each child on file descriptor number 0 (zero). When the last child in the group exits, Supervisor will close the socket.

All the options available to [program:x] sections are also respected by fcgi-program sections.

[fcgi-program:x] Section Values

[fcgi-program:x] sections have a single key which [program:x] sections do not have.

socket

The FastCGI socket for this program, either TCP or UNIX domain socket. For TCP sockets, use this format: tcp://localhost:9002. For UNIX domain sockets, use unix:///absolute/path/to/file.sock. String expressions are evaluated against a dictionary containing the keys "program_name" and "here" (the directory of the supervisord config file).

Default: No default.

Required: Yes.

Introduced: 3.0

socket_owner

For UNIX domain sockets, this parameter can be used to specify the user and group for the FastCGI socket. May be a UNIX username (e.g. chrism) or a UNIX username and group separated by a colon (e.g. chrism:wheel).

Default: Uses the user and group set for the fcgi-program

Required: No.

Introduced: 3.0

socket_mode

For UNIX domain sockets, this parameter can be used to specify the permission mode.

Default: 0700

Required: No.

Introduced: 3.0

Consult :ref:`programx_section` for other allowable keys, delta the above constraints and additions.

[fcgi-program:x] Section Example

[fcgi-program:fcgiprogramname]
command=/usr/bin/example.fcgi
socket=unix:///var/run/supervisor/%(program_name)s.sock
socket_owner=chrism
socket_mode=0700
process_name=%(program_name)s_%(process_num)02d
numprocs=5
directory=/tmp
umask=022
priority=999
autostart=true
autorestart=unexpected
startsecs=1
startretries=3
exitcodes=0,2
stopsignal=QUIT
stopasgroup=false
killasgroup=false
stopwaitsecs=10
user=chrism
redirect_stderr=true
stdout_logfile=/a/path
stdout_logfile_maxbytes=1MB
stdout_logfile_backups=10
stdout_events_enabled=false
stderr_logfile=/a/path
stderr_logfile_maxbytes=1MB
stderr_logfile_backups=10
stderr_events_enabled=false
environment=A="1",B="2"
serverurl=AUTO

[eventlistener:x] Section Settings

Supervisor allows specialized homogeneous process groups ("event listener pools") to be defined within the configuration file. These pools contain processes that are meant to receive and respond to event notifications from supervisor's event system. See :ref:`events` for an explanation of how events work and how to implement programs that can be declared as event listeners.

Note that all the options available to [program:x] sections are respected by eventlistener sections except for stdout_capture_maxbytes and stderr_capture_maxbytes (event listeners cannot emit process communication events, see :ref:`capture_mode`).

[eventlistener:x] Section Values

[eventlistener:x] sections have a few keys which [program:x] sections do not have.

buffer_size

The event listener pool's event queue buffer size. When a listener pool's event buffer is overflowed (as can happen when an event listener pool cannot keep up with all of the events sent to it), the oldest event in the buffer is discarded.

events

A comma-separated list of event type names that this listener is "interested" in receiving notifications for (see :ref:`event_types` for a list of valid event type names).

result_handler

A pkg_resources entry point string that resolves to a Python callable. The default value is supervisor.dispatchers:default_handler. Specifying an alternate result handler is a very uncommon thing to need to do, and as a result, how to create one is not documented.

Consult :ref:`programx_section` for other allowable keys, delta the above constraints and additions.

[eventlistener:x] Section Example

[eventlistener:theeventlistenername]
command=/bin/eventlistener
process_name=%(program_name)s_%(process_num)02d
numprocs=5
events=PROCESS_STATE
buffer_size=10
directory=/tmp
umask=022
priority=-1
autostart=true
autorestart=unexpected
startsecs=1
startretries=3
exitcodes=0,2
stopsignal=QUIT
stopwaitsecs=10
stopasgroup=false
killasgroup=false
user=chrism
redirect_stderr=false
stdout_logfile=/a/path
stdout_logfile_maxbytes=1MB
stdout_logfile_backups=10
stdout_events_enabled=false
stderr_logfile=/a/path
stderr_logfile_maxbytes=1MB
stderr_logfile_backups=10
stderr_events_enabled=false
environment=A="1",B="2"
serverurl=AUTO

[rpcinterface:x] Section Settings

Adding rpcinterface:x settings in the configuration file is only useful for people who wish to extend supervisor with additional custom behavior.

In the sample config file, there is a section which is named [rpcinterface:supervisor]. By default it looks like the following.

[rpcinterface:supervisor]
supervisor.rpcinterface_factory = supervisor.rpcinterface:make_main_rpcinterface

The [rpcinterface:supervisor] section must remain in the configuration for the standard setup of supervisor to work properly. If you don't want supervisor to do anything it doesn't already do out of the box, this is all you need to know about this type of section.

However, if you wish to add rpc interface namespaces in order to customize supervisor, you may add additional [rpcinterface:foo] sections, where "foo" represents the namespace of the interface (from the web root), and the value named by supervisor.rpcinterface_factory is a factory callable which should have a function signature that accepts a single positional argument supervisord and as many keyword arguments as required to perform configuration. Any extra key/value pairs defined within the [rpcinterface:x] section will be passed as keyword arguments to the factory.

Here's an example of a factory function, created in the __init__.py file of the Python package my.package.

from my.package.rpcinterface import AnotherRPCInterface

def make_another_rpcinterface(supervisord, **config):
    retries = int(config.get('retries', 0))
    another_rpc_interface = AnotherRPCInterface(supervisord, retries)
    return another_rpc_interface

And a section in the config file meant to configure it.

[rpcinterface:another]
supervisor.rpcinterface_factory = my.package:make_another_rpcinterface
retries = 1

[rpcinterface:x] Section Values

supervisor.rpcinterface_factory

pkg_resources "entry point" dotted name to your RPC interface's factory function.

Default: N/A

Required: No.

Introduced: 3.0

[rpcinterface:x] Section Example

[rpcinterface:another]
supervisor.rpcinterface_factory = my.package:make_another_rpcinterface
retries = 1

Environment Variable Interpolation

There may be a time where it is necessary to avoid hardcoded values in your configuration file (such as paths, port numbers, username, etc). Some teams may also put their supervisord.conf files under source control but may want to avoid committing sensitive information into the repository.

With this, all the environment variables inherited by the supervisord process are available and can be interpolated / expanded in any configuration value, under any section.

Your configuration values may contain Python expressions for expanding the environment variables using the ENV_ prefix. The sample syntax is foo_key=%(ENV_FOO)s, where the value of the environment variable FOO will be assigned to the foo_key. The string values of environment variables will be converted properly to their correct types.

Note

  • some sections such as [program:x] have other extra expansion options.
  • environment variables in the configuration will be required, otherwise supervisord will refuse to start.
  • any changes to the variable requires a restart in the supervisord daemon.

An example configuration snippet with customizable values:

[supervisord]
logfile = %(ENV_MYSUPERVISOR_BASEDIR)s/%(ENV_MYSUPERVISOR_LOGFILE)s
logfile_maxbytes = %(ENV_MYSUPERVISOR_LOGFILE_MAXBYTES)s
logfile_backups=10
loglevel = info
pidfile = %(ENV_MYSUPERVISOR_BASEDIR)s/supervisor.pid
nodaemon = false
minfds = 1024
minprocs = 200
umask = 022
user = %(ENV_USER)s

[program:cat]
command=/bin/cat -x -y --optz=%(ENV_CAT_OPTZ)s
process_name=%(program_name)s
numprocs=%(ENV_CAT_NUMPROCS)s
directory=%(ENV_CAT_DIR)s
umask=022
priority=999
autostart=true
autorestart=unexpected
exitcodes=0,2
user=%(ENV_USER)s
redirect_stderr=false
stopwaitsecs=10

The above sample config will require the following environment variables to be set:

  • MYSUPERVISOR_BASEDIR
  • MYSUPERVISOR_LOGFILE
  • MYSUPERVISOR_LOGFILE_MAXBYTES
  • USER
  • CAT_OPTZ
  • CAT_NUMPROCS
  • CAT_DIRECTORY